Steam-heating system.



W. G. SNOW 'STEAM HEATING SYSTEM.

APPLICATION FILED 050.10. 19m.

Patented Mar. 7, 1916.

' UNITED STATES PATENT OFFICE.

WILLIAM G. SNOW, F NEWTON CENTER, MASSACHUSETTS, ASSIGNOR TO WARREN WEBSTER-8a COMPANY, A CORPORATION OF NEW JERSEY.

STEAM-HEATING SYSTEM.

Specification of Letters Patent.

Patented Mar. 7, 191 6.

Application filed December 10, 1910. Serial No. 596,642.

the following is a specification.

My invention has reference to steam heating systems and consists of certain improve ments which are fully set forth in the following specification and shown in the accompanying drawings which form a part thereof.

The object of my invention is to provide a simple and effective construction of apparatus, adapted to low pressure or gravity systems of steam heating, which shall automatically control the steam pressure and return of the water of condensation to the boiler. i

-My invention consists in means for securing the above objects, said means being fully described herinafter and more particularly defined in the claims.

Referring to the drawings: Figure 1 is an elevation of a steam heating apparatus embodying my invention; and Fig. 2 is an enlarged sectional view of a portion of the air separating devices of the same.

2 is the steam boiler which is provided with a smoke flue 3 which may have a check draft damper 4. The ash pit is also provided with a draft door 5, the said door being adapted to control the draft below the grate, whereas the damper in connection with the chimney above referred to is to control the draft of the chimney.

8 is a damper regulator which is operated by the varying pressures which may exist in the boiler. This damper regulator is provided with a lever structure 9, from one end of Which a chain 10 extends down to the check draft damper 4:, and from the other end of whicha chain 11 extends down to the draft door 5. This mechanism operates in such manner that if the pressure in the boiler increases abnormally, the lever 9 is oscillated with the result of opening the damper 4 and closing the door 5 to lower the temperature of the furnace; and inversely, if the pressure falls too much, the damper 4 closes and the door 5 opens, to increase the draft and thereby raise the temperature of the furnace. In addition to the above damper mechanisms, I provide the chimney with a further auxiliary check draft damper 7 arranged in a draft check flue or inlet 6 for admitting air directly from the cellar into the chimney, the said damper 7 having no direct connection with the means which operate the damper 4. This last mentioned damper 7 is controlled by a static head or water column, preferably formed in connection with the return pipe of the heating system, so that when the water is forced up the column in response to the increased pressure in the boiler, the action of the rising water will automatically cause the damper 7 to be operated so that it will open and check the draft of the furnace of the boiler.

The steam from the boiler passes by the steam supply pipes 12 throughout the building, the steam risers extending to any points requiring to be steam heated. Steam is delivered from the steam risers to the radiators 13 by means of modulation valves 14, said valves being of a construction designed to regulate the quantity of steam delivered to the radiator in a given period of time.

15 are the return risers and are connected with the radiators by branch pipes 16 and which may have return traps 17, said return pipes delivering at the-bottom into a main return pipe 18 which discharges into an air separating chamber 19 for water and air, which for convenience, I will hereafter refer to as a trap arranged above the water level. The air separating and return trap 19 is above the water level of the boiler and is connected at its lower part by a pipe 21 which connects with the lower part of the boiler 2,

said pipe being preferably provided with a check valve 20 between the boiler and the said trap, to permit flow of water of condensation into the boiler, but prevent reverse flow from, the boiler into the trap. The trap 19 is further provided at the highest point of its chamber with an air vent pipe 26 leading to any convenient place and preferably provided with, a check valve 27, which ofiers practicallyv no resistance to the escape-of'the air but which prevents the inflow of air should a partial vacuum be created in the system by condensation of the steam in the radiators at times when the steam is shut off. The outlet from the trap 19 into the air "ent pipe 26 is provided with a normally open check valve 28, which may be made in the form shown in Fig. 2. Pivoted with the trap 19 is a float 22 which, upon being forced upward by the rise of water form the stand-pipe or water column 21 into the trap, will act upon the valve 28 to press it upon its seat, thereby preventing the escape of water of condensation through the vent pipe 26, and at the same time sealing the entire system against communication with the atmosphere. When this pivoted float 22 is moved under the influence of the water within the trap. it operates an arm 23, which in turn operates a chain 24: leading over suitable guides 29 to the weighted arm 25 of the auxiliary check damper 7 of the smoke pipe. When there is no water within the trap 19, the float 22 remains down, and when in this position, the check valve 28 is normally open to permit the free escape of air from the trap into the vent pipe 26. In addition to permitting the check valve 28 to open, the float 22 actuates the arm 23 to release the pull upon the chain 24, and thereby causes the auxiliary check damper 7 to close the communication with the atmosphere through the pipe 6, said damper being closed by direct means of its counterweight 25.

The operation of the system will now be understood :Assuming that the boiler is generating steam at the desired low pressure, namely, a pressure very slightly above atmospheric pressure, the automatic damper regulator 8 operating upon the check damper 4 in the chimney flue and the draft door 5, will tend to maintain the boiler under a given pressure. During this maintenance of the pressure, the steam is supplied by the supply pipes 12 and valves 14 to the respective radiators 13. The water of condensation and air which accumulates in the radiators pass through the automatic traps 17 into the return pipes 15 and thence by the main return 18 is delivered into the air separating and return trap 19. The air is here separated from the water and escapes by the vent pipe 26, while the water of condensation passes through the trap 19 and by the pipe 21 .returns to the boiler by gravity. It is to be understood that during this operation, there will be no water, or practically no water, in the trap 19, the said trap being arranged at an elevation above the water level in the boiler 2 sufficient to provide a normal head or static column of water above that of the level in the boiler suflicient to counterbalance the small steam pressure which is maintained in the boiler. The traps 17 are intended to be of the well known construction, which permit an escape of the water of condensation and air from the radiators into the return pipes, while preventing or restricting the passage of steam, the object being to limit the presence of the steam to the supply pipes and radiators. The interior construction of these automatic traps 17 is unimportant and may be any of the numerous forms which are now upon the market and known as return traps. Such traps are sometimes operated on the thermostatic principle,'while in other cases, they are operated by a float or by a pressure motor, and so far as my present invention is concerned, it is immaterial what form of return trap may be used. As a matter of fact, a returntrap may be omitted, if desired, and communication between the radiator and return be had by a restricted opening which may be controlled by a suitable static valve. All of these means arranged between the radiators and the returns are well known to those skilled in the art and need no further description. Assuming that, from any cause, thesteam pressure Within the boiler 2 should rise to an abnormal degree, such as might be caused by a sudden shutting off of a number of radiators, and thereby producing a less consumption of steam, the result would be to cause the automatic damper regulator 8 to come into play to open the check damper 4 and close the draft door 5 to a greater or less extent with the result of lowering the temperature. It is not possible, however, to cause a sudden stoppage of the generation of the steam, and consequently, aside from the normal regulation provided by the damper regulator 8, additional provision must be had to still further control the draft to more positively check the generation of the additional pressure. The means provided is, as before explained, the auxiliary check damper 7 controlled by the rise of the water on the return side of the system in the stand-pipe 21 and trap 19. As soon as the Water rises into the trap 19, it begins to open the auxiliary damper 7 and in that way checks the draft to a materially greater extent than is accomplished by the damper 4 and door 5, before referred to. It will be understood that if this pressure rises to such an extent as to fill the trap 19, there will be a tendency for the water to flow from the trap through the vent pipe 26 into the atmosphere, but this is prevented by means of the check valve 28 which is automatically closed by the float 22 as soon as the water tends to reach the level of the said valve and outlet from the trap into the vent pipe 26. While closing the escape of the water to the atmosphere through the vent 26, the air will also be prevented from passing into the return pipes 15 to the radiators, by reason of the presence of the check valve 28, and hence this valve will-remain sealed within the trap 19 so long as the excessive pressure existsin the steam boiler and the radiators are shut off. However, if the steam from the boiler is supplied in sufflcient volume to the radiators, it is evident that in due time, the Water of condensation in the return pipes 15 and 1-8, will with the pressure which will exist in said return pipes, overbalance the pressure within the boiler, and will pass through the trap 19 into pipe 21, the excess of water returning by the said pipe 21 through check valve 20 into the boiler to reestablish its proper level. It will be seen from this explanation that, whenever there is abnormal pressure in the boiler, the escape to the atmosphere is automatically closed before the water of condensation is free to return to the boiler, irrespective of its pressure when the pressure in the returns accumulates to balance the pressure-in the boiler. If there is an excessive pressure in the boiler 2, it is evident that the return of water to the boiler by accumulations of water of condensation in the returns, may take place without reducing the amount of water within the trap 19, and consequently without interfering with the proper action of the auxiliary check damper 7 which is tending to reduce the temperature of the furnace of the boiler.

As soon as the pressure in the boiler be comes sufliciently lowered, the water in the trap 19 automatically returns to a lower level and permits the float 22 to operate so that the check valve 28 may open to the atmosphere, and at the same time the auxiliary damper 7 may close the entrance of atmosphere in chimney 3. Gradual changes in pressure conditions in the boiler will be taken care of by the damper regulator 8 and the check damper and door which it controls, but in cases where the change of requirements in the heating are suddenly ef-. fected and the lowering of the temperature of the furnace cannot be accomplished with suflicient rapidity commensurate with the reduced demands, then the automatic trap 19 comes into play to still further control the temperature of the boiler furnace, as

well as to seal the system against escape to the atmosphere. I

I have shown my invention in a simple and conventional form in the drawings, but

I do not limit or restrict myself to the details shown, as these may be modified in various ways without departing from the spirit of the invention.

Having now described my invention what I claim as new and desire to secure by Letters Patent is 1. In a steam heating system, the combination of a plurality of radiators, a steam boiler, means to. supply steam to the radiators from the boiler, a return pipe leading from the radiators and communicating with the lower part of the boiler for returning the water of condensation thereto by gravity, a check valve in said return pipe to permit the water of condensation .to pass into the boiler while preventing back flow therefrom, means for regulating the degree of temperature of the furnace of the boiler, float actuated means controlled by the level of the water in the return side of the system .for controlling the means for regulating the degree of temperature of the boiler without alfecting the flow of water through the return pipe into the boiler, and separate automatically operating temperature regulating devices responsive to variations in the pressure in the boiler for varying the temperature of the furnace of the boiler to suit changes in steam pressure within the boiler,

but supplemented in its effect by the float restricting the passage of steam, a water column in communication withthe boiler below the water level and terminating in a chamber at its upper end above the level of the water in the boiler and said chamber in communication with the return pipe, a float device within the chamber adapted to be raised and lowered by the level of the water therein, means to control the generation of steam within the boiler controlled by the float device, an air vent to the atmosphere from the chamber to permit free escape of air from the chamber and return pipe into the atmosphere, a check valve on .the air vent normally operating to permit free pasa normally open valve independent of the check valve and operated by the float device for sealing the communication from the chamber into the air vent when the level of the water abnormally rises within the chamber.

3. In a steam heating system, the combination of a plurality of radiators, a steam boiler, means to supply steam to the radiators from the boiler, a return pipe leading from the radiators and communicating with the lower part of the boiler for returning the water of condensation thereto by gravity said pipe at all times normally open to the atmosphere and providing a static head arranged to discharge the water into the boiler when the pressure of said static head is to the chimney, a float actuated means controlled by the level of the static head in the return side of the system, said means comprisinga float and connecting means actuated thereby and extending to the check damper for opening the same when the float rises and vice versa, and a check valve independent of the float actuated means for permitting water to flow through the return pipe into the boiler but preventing the Water from the boiler passing into the return system to vary the static head.

. ing system for controlling the means for regulating the degree of temperature of the furnace without affecting the flow of water through the 'return pipe into the boiler, and separate automatically operating temperature regulating devices responsive to variations in pressure in the boiler for-varying the temperature of the furnace of the boiler to suit changes in steam pressure Within the boiler but supplemented in its eflect by the float controlled means for regulating the temperature.

5. In a steam heating system, the combination of a plurality of radiators, a steam boiler, means to supply steam to the radiators from the boiler, a return pipe separate from the means to supply steam to the radiators leading from the radiators and communicating with the lower part of the boiler, means between each radiator and the return pipe for permitting the passage of Water and air from the radiator into the return pipe but restricting the passage of steam, means in the return pipe close to the boiler for permitting constant returning of the water of condensation thereto by gravity except when abnormal pressure exists therein and at Which time the return side of the system is automatically closed ofl to the flow of wa- -ter from the boiler, means for regulating the degree of temperature of the furnace of the boiler, float actuated means controlled by the level of the water on thereturn side when closed ofl from free communication with the boiler, said means controlling the means for regulating the degree of temperature of the furnace Without affecting the automatic flow of Water through the return pipe into the boiler when the pressure of the Water on the return side of the system increases above the pressure in the boiler, normally open-vent devices for escape of air to the atmosphere from the return pipe communicating With the return side of the system above the float actuated means, and means operated by the float actuated means for sealing the vent pipe Whenever the water rises abnormally on the return side of the system due to excessive increase of pressure in the boiler said sealing means operating simultaneously with the action of reducing the temperature of the furnace.

In testimony of which invention, I hereunto set my hand.

WILLIAM G. SNOW.

Witnesses:

JOHN LAMBDEN, JOHN HARTLEY. 

